Riley Keough, Lisa Marie Presley,
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WEST HOLLYWOOD, CA - APRIL 27: (L-R) Riley Keough, Lisa Marie Presley, Linda Ramone and Billy Idol attend the Official After Party for 'Commando: The Autobiography of Johnny Ramone' hosted by Linda Ramone on April 27, 2012 in West Hollywood, California. (Photo by Sean tSabhasaigh/Getty Images)

LISA MARIE PRESLEY’s daughter RILEY KEOUGH crushed by cheating hunky beau, sources say AND mom has a message for the thesp who broke her daughter’s heart – Return to Sender!

The King’s wild-child granddaughter RILEY KEOUGH, 23, called off her engage­ment to “I Am Number Four” star ALEX PETTYFER after discovering he cheated on her with a sexy lingerie model, sources say.

But four-times-wed Lisa Marie never approved of the British hunk and is secretly thrilled the wedding is off, the sources add.

“Lisa Marie could so easily say, ‘I told you so,’ but she’s holding her tongue because she wants to be there for Riley,” revealed a close family friend.

“Lisa Marie knows all too well what it feels like when a relation­ship you had high hopes for goes awry. For now, she wants to provide as much comfort and support as she can for Riley.”

Riley met British actor Pettyfer, 22, on the set of the male stripper movie “Magic Mike,” and they got engaged in March after a six-month romance.

But as The ENQUIRER reported, Lisa Marie advised Riley not to mar­ry the actor, who’s known to have a bad temper and a vulgar mouth. She also feared Pettyfer just wanted a chunk of the estimated $300 million Presley family fortune.

“Riley was devastated when she heard Alex cheated on her in July with model Chelsea Heath,” said the source. “But for Lisa Marie, it’s the best thing that could have happened.

“She’s consoling Riley, but secretly she’s happy this guy is out of the picture.”